Catch basins are surface-level inlets to sewer systems that serve to allow storm water waste to enter a sewer system. Drainage and storm water is typically collected in catch basins buried in the ground. Water from rain or snow flows into the catch basin, where it is then diverted to a sewer or drainage line.
Grates are usually present at the top surface of the catch basins to help reduce the amount of debris that enters the basin. Filters or traps are often employed to remove various pollutants and solids from the water, such as to minimize or eliminate offensive odors, prevent large solids from entering the catch basin, reduce pollutants, etc. Indeed, governmental regulations often dictate the acceptable levels of various pollutants such as sediment, hydrocarbons and debris. Filters or traps containing activated carbon are commonly used for this purpose. Often the filters are removable, so that they can be replaced once the flow of liquid through the filter becomes impeded due to the accumulation of retentate.
Installation and maintenance of conventional catch basin traps for catch basins is problematic. They must be strategically located to inhibit or prohibit floating pollutants from entering the drainage pipe, yet be easily installed and provide accessibility to the pipe for maintenance and replacement. Most conventional oil/gas traps are made of cast iron, which is very heavy and makes installation extremely difficult. Often drilling into the concrete surrounding the drainage pipe is necessary, which is time-consuming and difficult. Additional installation hardware may be necessary, and installers must often remain in the catch basin (generally an underground confined space that is 4 feet in diameter and seven feet high) for extended lengths of time to install the trap. In addition, conventional gas traps do not maintain an effective seal to prevent floating pollutants from entering the drain pipe.
It therefore would be desirable to provide a gas trap that is lightweight, easy to install, requiring minimal or no installation hardware, and provides a reliable seal once installed.